The plane carrying United States Secretary of State Rex Tillerson touched the ground at the Jomo Kenyatta International Airport (JKIA) in Nairobi on Friday evening.
According to a statement given by State Department spokesman Steve Goldstein, Secretary Tillerson is not feeling well after long days of working on major issues back in the US.
Mr Tillerson was to hold an interactive meeting with Health CS Sicily Kariuki at the Pumwani Maternity Hospital on Saturday at 9am but the event did not take place.
The US diplomat, who arrived in Nairobi on Friday, had been due to visit the AIDS-relief programme PEPFAR on Saturday and also attend a ceremony marking 20 years since Al-Qaeda bombed the US embassies in Kenya and Tanzania, killing 224 people.
"Kenya is a country of tremendous opportunity", he said at a news conference after his arrival.
Tillerson's Saturday schedule included an event for PEPFAR, the US government-funded programme to fight HIV/AIDS, a visit to American diplomats at the USA embassy in Nairobi and a wreath-laying ceremony commemorating the 20-year anniversary of the deadly al-Qaeda bombing of U.S embassies in Kenya and Tanzania which killed 224 people.
He is also scheduled to visit Chad and Nigeria, where he will meet with President Muhammadu Buhari.
He was also to attend an event to highlight USA health assistance in Africa, and meet NASA leader Raila Odinga as well. "With a fast-growing GDP. a vibrant culture of entrepreneurship, and a regional economic leader, we are eager to find more ways to work with you".